Transmission Q

[Emeraldage]

I have a 89 7mge with w58.

If I got a 1jzgte from a jza70. I read I'd need a 2jzge flywheel and clutch. Do I also need a different bellhousing?

Also, if I used the r154 trans with the NA diff, the 4.3 (or whatever) it is, will my speedo read the right speed?

 

[te72]

You'll need a JZ flywheel, and also a JZ bellhousing. The clutch itself is specific to the transmission, not the engine.

As for the speed reading, that depends on the gear in your transmission that the speedo cable is spun by, AND your rear end, not to mention overall tire height. My transmission came out of a JZA70 with the 4.10 rear diff, I have a 3.73, with slightly taller tires, took me a couple times being pulled over to figure out that the higher the speeds, the further off my reading was on the gauge.

 

[Emeraldage]

Sigh why didn't I just get a turbo supra. So if I get a 1jz (Out of a supra because it's rear sump with an r154 and the 1st gen) stick that in my car, and get a new front piece of the drive shaft, would my speedo be wrong? I think mine is the 4.3 I believe. I do almost 3500 going 70.

 

[te72]

Finding a JZA70 engine is going to be a bit more of a challenge than just finding a 1jz that can be adapted to work. Just drops in the easiest.

As for the driveshaft, that has nothing to do with your speedo. It's the gear that is turned by the transmission in the tailshaft housing on the transmission itself. They made different gears for different setups. Mk3 Supras had 3.73, 3.91, 4.10, and 4.30 differentials, there is a corresponding gear for each. You need to get the proper gear for the transmission output (it's found inside the side of the trans, where the speedo cable plugs in on the passenger side there) for a 4.30 car. If you're using your current transmission with your 1j, then you don't need to change anything. Only reason I need to is because my transmission came with the engine out of the JZA70, which had a 4.10 differential, and I have a 3.73. Hence, MY speedometer is way off. Had I just re-used the same trans that was in the car, there would be no problem at all. Make sense?

 

[Emeraldage]

Yeah I get it. So if I got a r154 that's connected to a 1jz. And get a diff from a usdm Turbo it would still be off.? These little things make this so complicated xD. I'm probably just going to keep the w58 at this time. I read I need a 2jzge flywheel and clutch setup. Does this mean out of the is300 or na mk4 supra? They the same? Also. Will my current trans go right up to that? Or will I need a r154 to 1is bell housing?

 

[te72]

Yeah I get it. So if I got a r154 that's connected to a 1jz. And get a diff from a usdm Turbo it would still be off.? These little things make this so complicated xD. I'm probably just going to keep the w58 at this time. I read I need a 2jzge flywheel and clutch setup. Does this mean out of the is300 or na mk4 supra? They the same? Also. Will my current trans go right up to that? Or will I need a r154 to 1is bell housing?

You got it. If you get a JZA70 setup (engine and transmission) your speedo will likely be off unless the previous owner happens to have already swapped in the proper gear for the same diff ratio you have. Not likely though, but you can roughly tell your speed once you get a feel for the rpms and gears, just gotta do the math with a gearing calculator.

Flywheel is engine dependent, clutch is transmission dependent.

For the bellhousing, if you use a W58 trans, you will need the JZ to W58 bellhousing. Can get them from Driftmotion. In fact, calling Aaron up would be a good start to get what you need sorted out.